This article is from the Table Tennis (Ping Pong) FAQ, by ttennis@bu.edu with numerous contributions by others.
3.17.1 The expedite system shall come into operation if a game is unfinished
after fifteen minutes' play unless both players or pairs have scored
at least 19 points, or at any earlier time at the request of both
players or pairs.
3.17.1.1 If the ball is in play when the time limit is reached, play shall be
interrupted by the umpire and shall resume with service by the player
who served in the rally that was interrupted.
3.17.1.2 If the ball is not in play when the time limit is reached, play shall
resume with service by the player who received in the immediately
preceding rally of the game.
3.17.2 Thereafter, each player shall serve for one point in turn until the end
of the game and if the receiving player or pair makes thirteen good
returns the server shall lose a point.
3.17.3 Once introduced, the expedite system shall remain in operation for the
remainder of the match.
 
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